We divide 643093 by 80
We want to divide 643093 by 80.

On to step 1:
80 can be fit into 6 0 times, resulting in a remainder of 6.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtracting 0 from 6 leaves us with 6.
Include the next digit (4) from the dividend after 6, then repeat: 64 / 80

Advancing to step 2:
80 goes into 64 0 times with a remainder of 64.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we subtract 0 from 64, we get 64.
Include the next digit (3) from the dividend after 64, then repeat: 643 / 80

Moving on to step 3:
80 can be fit into 643 8 times, resulting in a remainder of 3.
The number 8 becomes the next digit in our result. 
Result so far: 8.0
If we take 640 away from 643, we end up with 3.
Grab the next digit (0) from the dividend, add it to 3, then carry on: 30 / 80

Advancing to step 4:
30 divided by 80 is 0 with a remainder of 30.
The number 0 becomes the next digit in our result. 
Result so far: 80.0
The remainder is 30 after subtracting 0 from 30.
Bring next digit (9) of the dividend behind the 30 and repeat the process: 309 / 80

Moving on to step 5:
80 goes into 309 3 times with a remainder of 69.
Put 3 as the next digit of the answer. 
Result so far: 803.0
If we take 240 away from 309, we end up with 69.
Bring next digit (3) of the dividend behind the 69 and repeat the process: 693 / 80

On to step 6:
If we divide 693 by 80, we get 8 and a remainder of 53.
Put 8 as the next digit of the answer. 
Result so far: 8038.0
If we subtract 640 from 693, we get 53.
Since there are no more digits in the dividend, we add a zero to the remainder making it 530, and continue the process.

Going ahead to step 7:
The number 80 fits into 530 6 times, leaving a remainder of 50.
Write down 6 as next digit of the result. 
Result so far: 8038.6
If we take 480 away from 530, we end up with 50.
Since there are no more digits in the dividend, we add a zero to the remainder making it 500, and continue the process.

Going ahead to step 8:
If we divide 500 by 80, we get 6 and a remainder of 20.
Put 6 as the next digit of the answer. 
Result so far: 8038.66
Subtracting 480 from 500 leaves us with 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

The final result is 8038.66 with a remainder of 0.02.